Okay... I’ll try to explain it as simple as possible. Outdoor clothing that you wear in a mountain can be roughly divided into five types. First of all, there’s something called a base layer. For the base layer, you should choose the ones that dry quick since it’s the layer that is supposed to fit tight to your skin.

“Polartec alpha jacket” is also for the middle layer. Polartec Alpha fabric has been gathering attention these days and simply put, it is a knit fabric with polyester fibers woven into a gauzelike thin mesh cloth. Polartec Alpha jacket has this fabric lined on the inside, so it keeps you warm and at the same time, it’s highly breathable and quick drying. What is more, it is a sweat-wicking fabric too, allowing it to be also suitable for vigorous physical activities including trail running, backcountry skiing, and alpine climbing.

Zzzz

おっと。

There she goes again.

はっ！次のはわかりますよ。防風ですよね。いわゆるシャカシャカ。

I’m awake! I know the next one. Wind-resistance, right? The ones that make the crinkly sound.

Exactly. It’s what you’d call a windbreaker or a softshell. Wind draws heat from your body more than you think and that is why this layer is important for the times like when you’re hiking on mountain ridges. You will be taking this jacket on and off quite frequently.

Right. These were the 3 main types of outdoor clothing for when you are active. You use these 3 layers effectively by mix and matching your clothes, depending on the temperature. Let’s suppose that the temperature is relatively high, but it’s windy. What would you do?

ベースレイヤーはさすがに脱げないんで、その上にウィンドブレーカーを羽織る！

I can’t take off my base layer, so I’d wear a windbreaker on top of it!

Well done. This is only the minimum, but you’ve probably got the basic idea of layering. The other two are thermal insulation and water resistance. To protect yourself against the cold, down jackets are perfect since it is heat retaining, and for water resistance, you should wear a hardshell.

ダウンジャケット系はどんな時に着るんですか？

When do I wear a down jacket?

休憩時とかテントの中とかだね。上からガバッと羽織れるよう、やや大きめのものを選ぶといい。

For example, when you’re having break or in the tent. It’s better to choose a bigger size so that you can easily wear it on top of everything.

Yeah, you said you were using it for jogging last time (Lesson 2), but I see that you’ve grown! The shape of the hood is important to protect yourself from the rain effectively, and it is also important to choose a highly breathable hardshell jacket because the heat can easily build up inside. These two types of jackets usually stay in the backpack when you are active, so lightness is another essential factor.

なるほど！なんとなくレイヤリングわかってきました！

That makes sense! I’m starting to get what layering is!

寒さや暑さの感じ方は個人差がかなりあるから、これを参考に自分にピッタリの組み合わせを見つけるのが大切だね。

Perception of heat and cold varies from person to person, so it is important for you to find your best combination using what you have learned today.

Isshi イッシー

Plays the teacher role in this program. A 15-year experienced hiker who heads out to the mountains under the pretext of a “field test” every time he buys a new outdoor gear. A mid-career staff at and wander, who realized that he gained much more weight himself than the weight he succeeded to save over the past 10 years by lightening the gears.

Ukiko ウキコ

Plays the student role in this program. Although she is interested in backpacking
trips, she is a new recruit at and wander and still has a lot to learn. Fluent speaker of
English and well-versed in fashion but tends to get panicked when she hears too many technical
outdoor terms.